In the past, many different devices for walking on water have been constructed to simulate the natural walking motion. Prior attempts at creating a foot-worn floatation/propulsion system have yet to produce a water-walking device that enables a human to simulate walking while propelling the device efficiently.
The act of walking, on land or on water, can be broken down into a sequence of coordinated basic movement pairs (each pair comprising a left leg movement and a right leg movement). There are four basic movements: Forward, an actual forward movement of the first leg and foot; Backward, the backward push against the resistance of the ground during which the second foot does not actually move; Up, the lifting the first leg off the ground or un-weighting of the leg during the movement; and Down, applying one's weight on the first leg. The act of walking naturally requires the smooth transition from one action to the next, and from one leg to the next. Any water-walking device should allow for all four movements in the normal sequence and with the natural timing a human has learned when walking on land.
A typical prior water walking device includes two elongated floats and some sort of variable resistance propulsion mechanism, typically having a multitude of either small rotatable flaps or fixed, rearward facing cups, pouches, or scoops. The typical prior float is generally flat bottomed and straight sided and the typical prior propulsion mechanism does not provide maximum resistance against the water at the point in the walking cycle when it is needed. Moreover, these mechanisms remain submerged during use of the water walking device, thereby providing resistance against forward motion. These devices sometimes include an oar for rowing the water-walking device. However, the oars do not operate well with the natural walking motion.
Some prior devices include a tethering mechanism to keep the floats from separating. Many of these mechanisms are overly constraining—that is, rather than just preventing excessive transverse separation, they instead prevent the user's feet from moving in at least some of the degrees of freedom possible on land. Typically, the tether mechanism, if present, either inhibits a full and natural stride (i.e., the length of a step), introduces friction into what is normally a frictionless forward leg movement, prevents the redirection of a forward stride (yaw) (as is needed for turning), or inhibits the required Up and Down leg movements.
It is therefore desirable to design a water-walking device that efficiently travels over water using the natural walking motion.